Combination-tool.



'1. H. ROBERTS.- COMBINATION TOOL.

Witnesses APPLICATION FILED OCT. 13. 1916.

Patented Oct. 16, 1917.

enter Attorneys l State JAMES H.

ROBERTS, OF CHARLESTON,

SOUTH CAROLINA.

COMBINATION-TOOL.

Application filed October 13,

To all whom it may concern:

Be it known that 1, JAMES H. ROBERTS, a citizen of the United States, residing at Charleston, in the county of Charleston and of South. Carolina, have invented a new and useful Combination-Tool, of which the following is a specification.

This invention relates to combination tools, one of its objects being to provide a eometrical instrument simplified to such a degree that knowledge of a few simple rules will enable the user to accomplish results ordinarily necessitating the employment of the square, compass and protractor.

'Another object of the invention is to provide a novel arrangement of suitably designated graduations designed to save time and enable the operator to arrive at results with the minimum calculation and drafting.

A still further object is to provide a geometrical tool especially useful to carpenters, cabinet-makers, sheet metal workers and in fact all mechanics who find it necessary in the course of their work to lay 0E angles. 5 A further object is to provide a tool of this character which can be used as inside and outside calipers.

With the foregoing and other objects in View which will appear as the description 30 proceeds, the combithe invention resides in nation and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the '35 invention herein disclosed, can be made within the scope of what is claimed, without departing from the spirit of the invention.

In the accompanying drawings the preferred form of the invention has been shown.

In said drawings Figure 1 is a face view of the tool. Fig. 2 is an edge view thereof. Referring to the figures by characters of reference 1 designates a blade having a straight edge along which are arrange graduations indicating inches or other units of measurement and fractions thereof. One end of this straight edge is recessed as at 2 and terminates in a point 3 while the 0pposed edge is rounded directly back of the point as shown at a.

A segment 5 is extended from the blade 1 and a stud 6 projects from the blade and is concentric with the segment. On this stud is adjustably mounted another blade 7 having a series of graduations along one edge Specification of Letters Patent.

' the two blades can Patented Got. 16, 191?.

1916. Serial No. 125,437.

thereof indicating inches or other units of measurement and fractions thereof. Formed in the opposed edge of this blade 7 at one end thereof is a recess 8 extending up to a point 9 corresponding with the point 3, the opposed edge of the blade being rounded back of the point, as indicated at 10. Thus it will be seen that the two points 3 and'9 are extended in opposite directions. The other end of the blade 7 has a point 11 adjacent which is formed a shoulder 12 terminating at a straight edge 13 which is parallel with the graduated straight edge of the blade 7. A clamping nut 14 mounted on the stud 6 and by means thereof be held against angular adjustment relative to each other.

Suitably indicated on the segment 5 is an arcuate series of graduations through 180. A series of designating numerals is arranged between these graduations and the arcuate edge of the segment.

and these numerals are used to indicate degrees, said numerals ranging from zero at one end of the series of graduations to the numeral 180 at the other end of said series. Another series of numerals is employed for indicating one-half of the series of graduations 15. This second series of designating numerals is preferably located under the graduations and the numerals, ranging from zero to 90 are disposed oppositely to the first series of numerals so that the character zero will be directly under the numeral 90 of the first series of numerals, while the numeral 90 will be under the character zero of the first series of numerals.

Another series of graduations indicated generally at 16 is indicated on the segment 5 and is concentric with the series 15. These graduations 16 are arranged in two groups extending toward each other and are designated by numerals indicating inches or other units of measurement. The first graduation d vof each group is indicated by the character zero and other numerals ranging from one upwardly are provided for designating certain of the other graduations, it being understood that the two groups of graduations are oppositely disposed as shown in Fig. 1.

As hereinbefore pointed out, the tool can be used as calipers or as a means for laying off timbers. When used as calipers the blades 1 and 7 can be adjusted angularly toward or from each other. When to be used 15 extending as outside calipers the arts are disposed as shown in Fig. 1 and t e right hand group of graduations 16 will be'readable in connection with the straight edge 13 to indicate the distance between the points 3 and 9 in inches or fractions thereof. By swinging the blade 7 across the blade 1, the tool can be used as inside calipers and the straight edge 13 can then be read in connec tion with the left hand group of graduations 16 to determine the interior measurement of the object to which the calipers are fitted.

Should it be desired to cut a rafter, the upper blade of the instrument should be turned until the pointer 11 and the cooperating graduations 15 indicate the desired pitch. This will give the bottom or foot cut of the rafter. To find the top or crown cut, the pointer 11 should be turned to the gradua tion designated by the corresponding number of the inner series. For example, if the pitch is 40, then the indicator should be set so that the pointer 11 will designate the graduation indicated by the numeral 40 of the outer or upper series. This will give the bottom out. The instrument shouldthen be readjusted until the pointer 11 is brought to the gradualie indicated by the numeral 40 of the inner series which will give the top out of the rafter. Hip and valley rafters are approximately 10 more obtuse than side rafters. Consequently if side rafters are pitched approximately at 40, the hip or valley.rafters will be pitched 30.

Cripple rafters have their top and bot- I toms cut the same as the side rafters but the angle out which fits against the hip or valley rafter should always be approximately 10 more acute than the crown or upper end of the rafter. For example, if the crown cut is 40 on the inner circle of graduations 15, then the angle cut of the cripple rafter would be approximately-50 on the same inner circle. Braces and stair horses are out upon the same principle as rafters. The miter line of any angle is exactly one half the angle shown by the indicator. For example, if an angle is 90 then will cut the miter.

From the foregoing it will be apparent that the instrument Will be found of considerable utility in laying ofi' angles of various kinds. Although it will be found of considerable advantage to men of technical education, it is especially advantageous for use by the ordinary journeyman mechanic of limited education who is thus enabled to lay out work that would otherwise be impossible for him to accomplish. The instrument can also be used as a protractor in addition to its use as calipers, as hereinbefore pointed out.

What is claimed is A tool of the class described, including a blade having a straight edge provided with graduations to indicate units of measure a segment extending from the other edge of said blade and having an arcuate series of graduations adjacent its periphery and extending through 180, there being charac ters between said graduations and the periphery of the segment for designating the degrees of the arc, said characters ranging from 0 to 180, there being an additional series of characters at the other side of the series of graduations and ranging from 0 to 90, the 0- character being used to designate the same graduation designated by the numeral 90 of the first series of characters and the numeral 90 of said second series of characters being used to designate the same graduation as the character 0 of the first series of graduations, and a. second blade pivotally mounted on the first mentioned blade at a point concentric with the arcuate series of graduations, said second blade having a pointer at one end adapted to indicate any one of the graduations.

In testimony that I claim the foregoing as my own, I have hereto aiiixed my signature in the presence of two witnesses.

JAMESH. ROBERTS.

Witnesses:

M. L. BLACKBURN, C. G. HOLLAND. 

